1332080 (1) 玖、發明說明 【發明所屬之技術領域】 本發明係關於將保護薄膜黏著於偏光板上之保護薄膜 黏著偏光板之缺陷檢查方法。 【先前技術】 偏光板係做爲構成液晶顯示裝置之光學零件之一而有 用。偏光板，一般而言係於偏光薄膜之兩面以黏著劑貼附 _ 保護膜，而以此貼附有保護膜之構造使用於液晶顯示裝置 。偏光板爲了避免刮傷等等，故於其兩面更貼附保護薄膜 ’而作爲保護薄膜黏著偏光板來進行檢查，運送，保管等 。此保護薄膜係於組裝液晶顯示裝置時從偏光板剝離並拋 棄。 另外，於偏光板之一面或是兩面所設置之黏著劑層， 係爲了將偏光板黏著於液晶單元而使用，並多係直接被組 裝於液晶顯示裝置者。 φ 有關保護薄膜黏著偏光板，若具有因異物等所產生之 缺陷，則成爲液晶顯示裝置之顯示缺陷，故於出貨等時檢 查作業係不可欠缺。檢查，譬如係相對於檢查用之偏光板 ’而將欲檢查之保護薄膜黏著偏光板，以正交偏光（ cross nicol )配置、亦即將此等之偏光軸方向配置於正交 狀態，並照射從光源來的光，將透過光之畫面藉由目視或 是攝像機來進行觀察之方法。此等之偏光板由於係成爲正 交偏光配置’故而’透過欲檢查之保護薄膜黏著偏光板後 5 -5- (2) 1332080 的光，係藉由檢查用偏光板來完全遮斷，但是，當於欲檢 查之偏光板之檢查用偏光板側存在有異物等之缺陷時，其 缺陷係作爲明亮之部分來被觀察到，藉此將可檢查缺陷。 而，相反側之缺陷，係將欲檢查之偏光板反向，而可藉由 相同檢查來進行（譬如，參考專利文獻1及專利文獻2) [專利文獻1] g 特開2000-206327號公報（段落「0002」） [專利文獻2] 特開200 1 -34983 9號公報（段落「0012」及段落「 0013」） 記載於專利文獻1及專利文獻2之方法雖然係優越之 方法，但是雖然能檢測出在欲檢查之保護薄膜黏著偏光板 之偏光薄膜和檢查用偏光板之間有缺陷，卻無法斷定此缺 陷係位於黏著劑層或是位於保護薄膜。其結果，即使檢測 φ 出缺陷，但對於確認出其缺陷產生之詳細原因上，係頗費 時間，同時，於保護薄膜即使有缺陷，但由於使用時將被 除去，因此會不必要地被判斷爲不良品》 本發明之目的，係在於提供一種可易於判定是否爲保 護薄膜之缺陷的保護薄膜黏著偏光板之缺陷檢查方法。 【發明內容】 本發明者爲了解決有關課題，努力檢討關於保護薄膜 黏著偏光板之缺陷檢查方法之結果，係發現於暗的畫像之 -6- d) (3) (3)1332080 中，被週期性或連續性所檢測出之明亮部分，係爲由於保 護薄膜之缺陷所產生者，故完成本發明》 亦即，本發明，係在將於偏光板之兩面黏著保護薄膜 之保護薄膜黏著偏光板、及檢查用偏光板，於光源和攝像 機之間作正交偏光（cross nicol)配置，並以攝像機攝影 ，再經由以攝像機所得到之暗的畫像中之明亮部分的有無 ，來檢查保護薄膜黏著偏光板之缺陷的方法之中，具備有 以下特徵：將暗的畫像中而週期性或是連續性地被檢查出 來之明亮部分，判斷爲因保護薄膜之缺陷所導致者。 【實施方式】 圖1表示保護薄膜黏著偏光板之例子之剖面模式圖。 偏光板（1)係於偏光薄膜（11)之兩面，將保護膜 (12)藉由黏著劑層（13)來接著。偏光子薄膜（11)譬 如係使用有藉由碘或是雙色性材料所染成之聚乙烯醇（ PVA)等之乙烯醇系樹脂薄膜，其厚度通常爲1〇〜30/zm 程度。作爲保護膜（12) ’譬如係以使用3醋酸纖維素（ TAC ) ，2醋酸纖維素（DAC )等之纖維素系樹脂，或是 聚丙烯酸系樹脂’聚對苯二甲酸乙二酯（PET)等之酯系 樹脂等’其厚度通常爲10〜180 "m程度。做爲黏接偏光 薄膜和保護膜之黏接劑，譬如係使用聚乙烯醇系之黏著劑 等。 於偏光板（1)之雙面係藉由黏著劑層（4，5)而黏 者保護薄膜（2，3)。而做爲保護薄膜係以使用無配向薄 (4) 1332080 膜或是單軸延伸薄膜。保護薄膜之材質，譬如如PET等 之酯系樹脂’聚乙烯（PE) ’聚丙烯（PP)等之聚烯系 樹脂’聚丙烯酸樹脂'，TAC，DAC等之纖維素系樹脂等。 同時，保護薄膜之厚度，通常爲10〜100//m程度，最理 想係3 0~5 0 v m程度。保護薄膜爲單軸延伸薄膜時，係使 延伸軸方向和偏光薄膜（11)之偏光軸方向一致而黏著。 保護薄膜（2)亦稱之爲分離薄膜，使用於液晶顯示 φ 裝置等時爲剝離，拋棄。此時，黏著劑層（4)通常爲殘 留於偏光板（1)之表面，使用於偏光板之和液晶單元等 之貼合。因此’於黏著劑層（4)處若是具有灰塵等之異 物，則會降低液晶顯示裝置之功能。 ' 作爲構成黏著層（4)之黏著劑，若是爲透明且均勻 之黏著劑時，則並不被特別限定，但在易於組裝於液晶顯 示裝置此點上，一般係使用感壓型黏著劑。作爲如此之感 壓型黏著劑，譬如以聚丙烯酸系感壓型黏著劑，聚氨酯感 • 壓型黏著劑爲例子。 保護膜（3)亦稱之爲保護薄膜，使用於液晶顯示裝 置等時爲剝離，拋棄。黏著劑層（5)係使用對於保護薄 膜而黏著性較爲強者，當剝離保護薄膜時，係不殘留於偏 光板地黏著於保護薄膜而剝離，拋棄。保護薄膜（3)本 身具有黏著性時，係不藉由黏著層（5)而直接黏著於偏 光板（1 )。 通常，係在事先作了檢測而無缺陷之偏光板（1 )上 黏著保護薄膜（3)。因此，就算是在對於保護薄膜黏著 -8 - ⑧ (5) 1332080 偏光板（6)作檢查而檢測出缺陷時，亦如上述 的’除了黏著劑層（4)之外，由於保護薄膜（ 黏著劑層（5 )最終係被剝離、廢棄，故存在於 缺陷不會成爲致命性的缺點。 圖2爲表示保護薄膜黏著偏光板之缺陷檢查 式圖。於（A)之中，於光源（22)和攝像機（ ，係將保護薄膜（2 )置於攝像機側地而配置保 著偏光板（1)，於保護薄膜（2)和攝像機（23 係配置有檢查用偏光板（21)。於此，保護薄膜 板（1)之偏光薄膜（11)，和檢查用偏光板（ 作正交偏光（cross nicol)配置，亦即是被配置 之偏光軸方向相互正交之狀態。從攝像機而來之 ，係於畫像處理裝置（24 )處被作處理，並檢測 而輸出於監視器。 又，於圖2中，省略保護薄膜黏著偏光板！ 接著劑層（1 3 )，及黏著劑層（5 )。 從光源（22)而來的光，係選擇性透過偏光 )之偏光軸方向之偏光成分，於偏光薄膜（11) 偏光板（21)之間，若無刮傷或異物等之缺陷， 護薄膜黏著偏光板的光，係被檢查用偏光板所阻 像機之攝影畫像將呈現出暗的顔色。而於偏光薄 和檢查用偏光板（2 1 )之間若有缺陷時，則將會 分之偏光方向，而透過檢査用偏光板，並於較暗 中呈現出較爲明亮部分。 所述一般 2，3 )及 此等處之 方法之模 2 3 )之間 護薄膜黏 )之間， 黏著偏光 21)，係 爲使此等 畫像信號 出缺陷， 〔1 )中之 薄膜（1 1 和檢查用 則透過保 止，而攝 膜（11 ) 改變該部 攝影畫像 -9- (6) 1332080 藉由檢測出此明亮部分，而檢測出保護薄膜黏著偏光 板之偏光薄膜（U)和保護薄膜（2)之間的缺陷。同時 ，若將保護薄膜黏著偏光板轉爲相反面時，將檢測出偏光 薄膜（11)和保護薄膜（3)之間的缺陷。 圖2 ( B )係於光源（22 )和攝像機（23 )之間，將 保護薄膜（3)置於攝像機側，而配置保護薄膜黏著偏光 板（1 )，並於保護薄膜（2 )和光源（22 )之間，配置檢 φ 查用偏光板（21)。於此，保護薄膜黏著偏光板（1)之 偏光薄膜（11)，和檢查用偏光板（21)，係和（A)同 樣地被作正交偏光（cross nicol)配置。 此種情況，和（A )相同地亦檢測出缺陷。 一般係使用CCD攝像機來做爲攝像機，攝影所得之 ' 畫像信號，係於畫像處理裝置中，利用電腦系統而進行畫 像處理，並檢測出缺陷。 圖3，圖4爲檢測出了缺陷之畫像模式圖。於圖3之 φ 中，白箭頭係表示檢查時之薄膜前進方向，而白圓形符號 係表示缺陷，並展示有：在從薄膜之側部而距離W1之位 置處，以長度L之間隔而周期性地呈現有缺陷之例子。又 ，在圖4中，係展示有：於以白箭頭所示之檢查時之薄膜 前進方向上而出現有連續帶狀之缺陷的例子。此種缺陷， 係爲由於保護薄膜之缺陷所導致者，而爲於保護薄膜之貼 合工程等時產生於保護薄膜處者。而，黏著劑層之缺陷由 於係爲由灰塵或是塵埃等所造成，因此，通常如此之周期 性或是連續性缺陷係不會出現於黏著劑層處。除此之外， -10- (7) (7)1332080 不定期所出現之缺陷，係會出現於黏著劑劑層或是保護薄 膜處。 通常，對畫像信號作處理所得到之亮度，由於係針對 每畫素或是每畫素群所求得，故而，係事先設定臨界値， 並將超越設定臨界値之亮度作爲缺陷來加以判定。 關於是否具有周期性或是連續性缺陷一事，係如同下 述一般而作檢測。首先，事先對於檢查對象薄膜藉由直行 偏光（cross nicol )等進行自動檢查，並將相對於薄膜之 進行方向（長度方向）而直角方向（寬方向）之缺陷位置 係爲相同且於長度方向上具有周期性之缺陷檢測出來。將 檢測出之缺陷以目視檢查，當其缺陷爲存在於保護薄膜上 時，係將其週期設定成缺陷週期長度。通常，缺陷週期長 度，係與於貼合工程等所使用之捲筒之圓周長相同。其次 ，將本發明之檢查所得之畫像的薄膜之長度方向及寬度方 向，分別分割成一定之大小的格子。於薄膜之進行方向上 ，設定連續有一定個數之格子的方塊。方塊長度係設爲於 上述所決定之缺陷週期長度。當於方塊內之格子檢測出缺 陷’並連續而於下一個方塊的相同位置之格子檢查出缺陷 時，判定爲周期性或連續性之缺陷。 —般’於3至7個方塊，連續檢測出缺陷時，其以後 之缺陷’係將該缺陷視爲保護薄膜之缺陷，並將保護薄膜 黏著偏光板判定爲不良品，而可去除。 [實施例] -11 - (8) 1332080 以下’係藉由實施例來詳述本發明，但是本發明並非 限定於此等之實施例。 實施例1 在於其中一面上具備有黏著劑層（4)之偏光板[TAC 薄膜/碘染色之PVA薄膜/TAC薄膜](1)之黏著劑層上， 貼附保護薄膜（分離薄膜）（2)，並在與設置有黏著劑 φ 層之側之相反面上貼附保護薄膜（3 )，而得到保護薄膜 黏著偏光板（6)，針對此保護薄膜黏著偏光板（6)(圖 1 )，進行了缺陷檢查。 於光源（22 )和攝像機（23 )之間，將保護薄膜（2 • )置於攝像機側地配置保護薄膜黏著偏光板（1 )，於保 ' 護薄膜（2)和攝像機（23)之間，配置檢查用偏光板（ 21)，保護薄膜黏著偏光板（1)之偏光薄膜（11)與檢 查用偏光板（21)成爲正交偏光（cross nicol)配置。以 φ 攝像機（23 )攝影，將其畫像信號以畫像處理裝置（24 ) 進行處理，而檢測出缺陷。 於畫像檢查時之薄膜進行方向上’設定與在保護薄膜 之貼合工程中所使用之滾軸之圓周爲相同長度（5 02nm ) 之方塊，檢查了 20m之寬度爲125〇mm之薄膜》 於此，對於檢查出全部缺陷的情況’及在對於5個方 塊而連續地檢測出缺陷後，將該缺陷除外而進行了檢查的 情況，計算其缺陷率。 檢查出全部之缺陷：2.26個/m2 ⑤ -12- (9) 1332080 去除週期缺陷：0.47個/m2 在對此保護薄膜黏著偏光板而以顯微鏡作了觀察後， 於保護薄膜（2)檢測出長度502mm週期之瑕疵。 [發明效果] 若藉由本發明之方法，則可容易地判斷是否爲保護薄 膜之缺陷，且可縮短檢討出缺陷產生之詳細原因所需的時 間，同時可避免不必要之不良品的產生。 φ 【圖式簡單說明】 圖1爲表示保護薄膜黏著偏光板之例的剖面模式圖。 圖2爲表示保護薄膜黏著偏光板之缺陷檢查方法的模 · 式圖。 圖3爲表示檢測出缺陷之畫像的模式圖。 圖4爲表示檢測出缺陷之其他畫像的模式圖。 【符號之說明】 1 ............................偏光板 2 ............................保護薄膜（分離薄膜） 3 ...........................保護薄膜（保護（PROTECT)薄膜） 4 ............................黏著劑層 5 ............................黏著劑層 6 ............................保護薄膜黏著偏光板 11...........................偏光薄膜 -13- (10) (10)1332080 12 ...........................保護膜 13 ...........................接著劑層 2 1...........................檢查用偏光板 22 ...........................光源 23 ...........................攝像機 2 4...........................畫像處理裝置1332080 (1) Field of the Invention The present invention relates to a defect inspection method for a protective film adhesive polarizing plate in which a protective film is adhered to a polarizing plate. [Prior Art] The polarizing plate is useful as one of the optical components constituting the liquid crystal display device. The polarizing plate is generally applied to a liquid crystal display device by attaching a protective film to the both sides of the polarizing film with an adhesive. In order to avoid scratches and the like, the polarizing plate is further attached with a protective film ‘ on both sides, and is attached to the polarizing plate as a protective film for inspection, transportation, storage, and the like. This protective film is peeled off from the polarizing plate and discarded when the liquid crystal display device is assembled. Further, the adhesive layer provided on one surface or both surfaces of the polarizing plate is used to adhere the polarizing plate to the liquid crystal cell, and is often incorporated directly into a liquid crystal display device. φ When the protective film is attached to the polarizing plate, if it has defects due to foreign matter or the like, it becomes a display defect of the liquid crystal display device. Therefore, the inspection operation is indispensable when shipping. For example, the protective film to be inspected is adhered to the polarizing plate with respect to the polarizing plate for inspection, and is arranged in a cross nicol, that is, the direction of the polarization axis is arranged in an orthogonal state, and is irradiated from The light from the light source is observed by visual or camera through the light. Since these polarizing plates are arranged in an orthogonal polarization configuration, the light of the 5-5-(2) 1332080 after the polarizing plate is adhered through the protective film to be inspected is completely blocked by the polarizing plate for inspection, however, When there is a defect such as a foreign matter on the side of the polarizing plate for inspection of the polarizing plate to be inspected, the defect is observed as a bright portion, whereby the defect can be inspected. On the other hand, the defect on the opposite side is reversed by the polarizing plate to be inspected, and can be performed by the same inspection (for example, refer to Patent Document 1 and Patent Document 2) [Patent Document 1] g-opening No. 2000-206327 (Paragraph "0002") [Patent Document 2] JP-A-200-34983 (paragraph "0012" and paragraph "0013") The methods described in Patent Document 1 and Patent Document 2 are superior methods, although It is possible to detect that there is a defect between the polarizing film of the protective film to be inspected and the polarizing plate for inspection, but it is not determined whether the defect is in the adhesive layer or in the protective film. As a result, even if the defect is detected by φ, it takes a long time to confirm the cause of the defect, and at the same time, even if the protective film is defective, it is removed at the time of use, and thus it is unnecessarily judged. The object of the present invention is to provide a defect inspection method for a protective film-adhesive polarizing plate which can easily determine whether it is a defect of a protective film. SUMMARY OF THE INVENTION In order to solve the problems, the inventors of the present invention have tried to review the results of the defect inspection method for the protective film-adhesive polarizing plate, which was found in the dark image of -6-d) (3) (3) 1332080. The bright portion detected by the property or the continuity is caused by the defect of the protective film, so the present invention is completed, that is, the protective film is adhered to the protective film which is adhered to the protective film on both sides of the polarizing plate. And checking the polarizing plate, performing a cross nicol configuration between the light source and the camera, and photographing the camera, and then checking the adhesion of the protective film via the presence or absence of a bright portion in the dark image obtained by the camera. Among the methods of the defect of the polarizing plate, there is a feature that the bright portion which is periodically or continuously detected in the dark image is judged to be caused by a defect of the protective film. [Embodiment] Fig. 1 is a schematic cross-sectional view showing an example of a protective film-adhesive polarizing plate. The polarizing plate (1) is attached to both sides of the polarizing film (11), and the protective film (12) is followed by the adhesive layer (13). The polarizing film (11) is a vinyl alcohol resin film such as polyvinyl alcohol (PVA) dyed by iodine or a dichroic material, and its thickness is usually about 1 〇 30 30 ° z. As the protective film (12) 'for example, a cellulose resin such as 3 cellulose acetate (TAC), 2 cellulose acetate (DAC), or a polyacrylic resin 'polyethylene terephthalate (PET) is used. The ester resin or the like has a thickness of usually 10 to 180 "m. As an adhesive for bonding a polarizing film and a protective film, for example, a polyvinyl alcohol-based adhesive or the like is used. On both sides of the polarizing plate (1), the protective film (2, 3) is adhered by the adhesive layer (4, 5). As a protective film, a non-aligned thin (4) 1332080 film or a uniaxially stretched film is used. The material of the protective film is, for example, an ester resin such as PET, a polyethylene resin such as polyethylene (PE) polypropylene (PP), a polyacryl resin, a cellulose resin such as TAC or DAC. At the same time, the thickness of the protective film is usually about 10 to 100/m, and it is most desirable to be about 30 to 50 v. When the protective film is a uniaxially stretched film, the direction of the extension axis and the direction of the polarization axis of the polarizing film (11) are aligned and adhered. The protective film (2) is also referred to as a separation film, and is used for peeling off and discarding when used in a liquid crystal display φ device or the like. At this time, the adhesive layer (4) is usually left on the surface of the polarizing plate (1), and is used for bonding the liquid crystal cell or the like to the polarizing plate. Therefore, if there is a foreign matter such as dust at the adhesive layer (4), the function of the liquid crystal display device is lowered. The adhesive which constitutes the adhesive layer (4) is not particularly limited as long as it is a transparent and uniform adhesive. However, in the point of easy assembly in a liquid crystal display device, a pressure-sensitive adhesive is generally used. As such a pressure-sensitive adhesive, for example, a polyacrylic pressure-sensitive adhesive or a polyurethane-based pressure-sensitive adhesive is exemplified. The protective film (3) is also called a protective film, and is peeled off and discarded when used in a liquid crystal display device or the like. The adhesive layer (5) is used for protecting the film and has a strong adhesiveness. When the protective film is peeled off, it is adhered to the protective film without leaving the polarizing plate, and is peeled off and discarded. When the protective film (3) itself has adhesiveness, it is directly adhered to the polarizing plate (1) without being adhered to the adhesive layer (5). Usually, the protective film (3) is adhered to the polarizing plate (1) which has been previously tested without defects. Therefore, even if a defect is detected by inspecting the protective film adhesion -8 - 8 (5) 1332080 polarizing plate (6), as in the above-mentioned 'except the adhesive layer (4), due to the protective film (adhesion) The agent layer (5) is finally peeled off and discarded, so that the defect does not become fatal. Fig. 2 is a diagram showing the defect inspection pattern of the protective film-adhesive polarizing plate. In (A), the light source (22) And the camera (the protective film (2) is placed on the side of the camera to hold the polarizing plate (1), and the protective film (2) and the camera (23 are arranged with the polarizing plate for inspection (21). a polarizing film (11) for protecting the film sheet (1), and a polarizing plate for inspection (for a cross nicol arrangement, that is, a state in which the direction of the polarization axis of the arrangement is orthogonal to each other. It is processed at the image processing device (24), and detected and output to the monitor. Also, in Fig. 2, the protective film is adhered to the polarizing plate! The next layer (1 3 ), and the adhesive layer (5) The light from the light source (22) is selectively transmitted The polarizing component in the direction of the polarization axis of the light) is between the polarizing film (11) and the polarizing plate (21). If there is no scratch or foreign matter, the light of the protective film adheres to the polarizing plate is blocked by the polarizing plate for inspection. The photographic image of the camera will show a dark color. If there is a defect between the polarizing film and the polarizing plate for inspection (2 1 ), it will be divided into the polarizing direction, and the polarizing plate for inspection will pass through. a relatively bright part is present in the dark. The general 2, 3) and the method 2 3 of the method of the method are between the protective film and the adhesive film 21), so that the image signals are defective. The film in [1] (1 1 and inspection are used to protect, and the film (11) changes the photographic image -9- (6) 1332080 By detecting the bright portion, the protective film is polarized. A defect between the polarizing film (U) of the board and the protective film (2). Meanwhile, when the protective film is adhered to the opposite side, the polarizing film (11) and the protective film (3) are detected. Defect. Figure 2 (B) is between the light source (22) and the camera (23) The protective film (3) is placed on the side of the camera, and the protective film is placed on the polarizing plate (1), and between the protective film (2) and the light source (22), the polarizing plate (21) for inspection is disposed. Thus, the polarizing film (11) of the protective film-adhered polarizing plate (1) and the polarizing plate (21) for inspection are arranged in a cross nicol in the same manner as (A). In this case, A) Defects are also detected in the same way. Generally, a CCD camera is used as a camera, and the image signal obtained by photography is attached to an image processing device, and image processing is performed using a computer system to detect defects. Fig. 3 and Fig. 4 are diagrams showing the pattern of the defect detected. In φ of Fig. 3, the white arrow indicates the film advancing direction at the time of inspection, and the white circle symbol indicates the defect, and is shown at a distance L from the side of the film at a distance W1. Examples of defects are periodically presented. Further, in Fig. 4, there is shown an example in which a continuous strip-shaped defect occurs in the advancing direction of the film at the time of inspection indicated by a white arrow. Such a defect is caused by a defect of the protective film, and is generated at the protective film when the protective film is bonded or the like. However, the defect of the adhesive layer is caused by dust or dust, and therefore, such periodic or continuous defects are not usually present at the adhesive layer. In addition, -10- (7) (7) 1332080 defects that occur irregularly may occur at the adhesive agent layer or at the protective film. In general, the brightness obtained by processing the image signal is determined for each pixel or for each pixel group. Therefore, the threshold 値 is set in advance, and the brightness exceeding the set threshold 作为 is determined as a defect. Regarding whether there is a periodicity or continuity defect, it is tested as follows. First, the inspection target film is automatically inspected by a straight nicol or the like, and the defect position in the direction perpendicular to the film (longitudinal direction) in the direction of the film (width direction) is the same and in the length direction. A defect with periodicity is detected. The detected defect is visually inspected, and when the defect is present on the protective film, its period is set to the length of the defect cycle. Usually, the length of the defect cycle is the same as the circumference of the reel used for the bonding work or the like. Next, the longitudinal direction and the width direction of the film of the image obtained by the inspection of the present invention are divided into lattices of a certain size. In the direction in which the film is made, a block having a certain number of grids is continuously set. The length of the block is set to the length of the defect cycle determined as described above. When the defect is detected in the grid in the square and the defect is detected continuously in the grid at the same position of the next square, it is judged to be a defect of periodicity or continuity. When the defect is continuously detected in 3 to 7 squares, the subsequent defect is regarded as a defect of the protective film, and the protective film-adhesive polarizing plate is judged to be a defective product and can be removed. [Embodiment] -11 - (8) 1332080 The following is a detailed description of the present invention by way of examples, but the invention is not limited to the embodiments. Example 1 A protective film (separation film) was attached to an adhesive layer of a polarizing plate (TAC film/iodine-dyed PVA film/TAC film) (1) having an adhesive layer (4) on one side thereof (2) And attaching a protective film (3) on the opposite side to the side on which the adhesive φ layer is provided, and obtaining a protective film adhered to the polarizing plate (6), and the protective film is adhered to the polarizing plate (6) (Fig. 1) , a defect check was performed. Between the light source (22) and the camera (23), a protective film (2) is placed on the camera side, and a protective film is adhered to the polarizing plate (1) between the protective film (2) and the camera (23). The polarizing plate (21) for inspection is disposed, and the polarizing film (11) of the protective film adhesion polarizing plate (1) and the polarizing plate (21) for inspection are arranged in a cross nicol configuration. The image is detected by the φ camera (23), and the image signal is processed by the image processing device (24) to detect the defect. In the direction of the film inspection, the film was set to the same length (5 02 nm) as the circumference of the roller used in the bonding process of the protective film, and a film having a width of 125 mm was inspected for 20 m. Here, in the case where all defects are detected, and after the defects are continuously detected for five squares, the defects are excluded and the inspection is performed, and the defect rate is calculated. Check all the defects: 2.26 / m2 5 -12- (9) 1332080 Removal cycle defect: 0.47 / m2 After the protective film was adhered to the polarizing plate and observed by a microscope, the protective film (2) was detected. The length of the period of 502mm. [Effect of the Invention] According to the method of the present invention, it is possible to easily judge whether or not it is a defect of the protective film, and it is possible to shorten the time required to review the detailed cause of the occurrence of the defect, and to avoid the occurrence of unnecessary defective products. φ [Simplified description of the drawings] Fig. 1 is a schematic cross-sectional view showing an example in which a protective film is adhered to a polarizing plate. Fig. 2 is a view showing a method of inspecting a defect of a protective film-adhesive polarizing plate. Fig. 3 is a schematic view showing an image in which a defect is detected. Fig. 4 is a schematic view showing another image in which a defect is detected. [Description of Symbols] 1 ............................Polarized Plate 2 ............. ...............protective film (separation film) 3 ........................... Film (PROTECT film) 4 ...........................Adhesive layer 5 ......... ...................Adhesive layer 6 ........................... .Protective Film Adhesive Polarizing Plate 11...........................Polarized Film-13- (10) (10)1332080 12 ... ........................Protective film 13 ....................... .... adhesive layer 2 1........................... Check polarizer 22 ......... ..................Light source 23 ...........................Camera 2 4 ........................... Image processing device
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